Ventilatory response at the onset of voluntary exercise and passive movement in endurance runners

Abstract

The present study was performed to examine whether or not the ventilatory response at the onset of voluntary exercise and passive movement in endurance runners is the same as in untrained subjects. Twelve long-distance runners belonging to the varsity athletic club and 13 untrained subjects of our university participated as subjects in this study. Maximum oxygen uptake was significantly higher in the endurance runner group [mean (SD) 70.8 (4.7) ml.kg-1.min-1] than in the untrained group [49.8 (6.3) ml.kg-1.min-1]. Cardiorespiratory responses during voluntary exercise and passive movement of alternate flexion-extension of the right and left legs for about 15 s at a frequency of about 60 rpm, were determined by means of breath-by-breath techniques. Minute inspiratory ventilation (VI), tidal volume (VT), respiratory frequency (fb), cardiac output (Qc), stroke volume (SV) and heart rate (HR) increased significantly immediately at the onset of voluntary exercise and passive movement. The incremental rate for VI was greater than that for Qc. Average values and standard deviations of changes in VI were calculated as the difference between the mean of the first and second breath and the mean of five breaths preceding the exercise or movement. The rates obtained in voluntary exercise and passive movement in the endurance runner group [2.34 (0.82) and 1.72 (0.71 l.min-1), respectively] were significantly (P < 0.05) lower than those in the untrained group [4.16 (2.66) and 2.71 (1.56 l.min-1), respectively]. Also changes in VT and HR were significantly lower in the endurance group than in the untrained group with regard to both voluntary exercise and passive movement. The results suggest that the magnitude of cardiorespiratory responses at the onset of voluntary exercise and passive movement in humans is influenced by chronic endurance training for long periods.

Breathing Frequency Changes at the Onset of Stepping in Human Infants

“…Rhythmic limb movements that have been confirmed to be largely passive in humans (Bell et al 2003) are associated with a rapid increase in the minute ventilation (Dejours et al 1959;Ishida et al 1994;Sato et al 2000) and frequency of breathing (Bell et al 2003;Ishida et al 1994;Miyamura et al 1997). Interestingly, subjects with clinically complete spinal cord injuries did not show the increase in minute ventilation with passive movements (Jaeger-Denavit et al 1973;Morikawa et al 1989) and those with incomplete lesions showed ventilatory changes that were intermediate between healthy controls and those with clinically complete spinal cord injuries (Jaeger-Denavit et al 1973).…”

Ventilatory and Heart Rate Responses at the Onset of Chair Rotation in Man

“…These data were stored on a hard disk unit, and analyzed afterward on a personal computer (NEC, PC-9821Xa, Japan). Breath-by-breath and beat-by-beat data were aligned with the onset of each turn, linearly interpolated between each breath or beat to yield a data point at each 1 s interval, and the ensemble average was done across all three repetitions [16,17]. The peak attained times of V .…”

Training-related changes in the R-R interval at the onset of passive movements in humans

“…However, the underlying neural cardiovascular mechanisms of training-related alterations in R-R interval responses at the onset of exercise are not understood. Thus, previous studies have addressed this issue considering the possibility of neural changes in the relative role of the muscle mechanoreflex and its inhibitory effect on cardiac vagal activity (8)(9)(10)(11)(12). Additionally, passive movement is widely employed to estimate the effect of the muscle mechanoreflex in humans (10,(13)(14)(15), because the effect of central command can be removed.…”

“…Additionally, passive movement is widely employed to estimate the effect of the muscle mechanoreflex in humans (10,(13)(14)(15), because the effect of central command can be removed. Human studies examining the influence of exercise training on the heart rate response at the onset of passive movement have used a cross-sectional design (11,12), making comparisons between trained and untrained subjects. These investigators noted that the heart rate increase throughout 20 s of passive movement is attenuated in endurance runners (11) and sprinters (12) compared to untrained subjects.…”

“…Human studies examining the influence of exercise training on the heart rate response at the onset of passive movement have used a cross-sectional design (11,12), making comparisons between trained and untrained subjects. These investigators noted that the heart rate increase throughout 20 s of passive movement is attenuated in endurance runners (11) and sprinters (12) compared to untrained subjects. Of note, a potential problem in trying to evaluate the relative importance of these mechanoreflex adaptations has been the inability to completely dissociate them from central adaptations.…”